1. Field of the Invention
The invention relates to pressure reduction, and more particularly to a variable pressure reducing device.
2. Description of the Related Art
Numerous applications of high pressure fluid systems require, at some point in the system, pressure reduction to allow safe handling of fluids. Referring to FIG. 1, U.S. Pat. RE37,153E discloses a conventional pressure reducing device that includes a housing 11. The housing 11 includes a barrel 111 and a pair of tubes 112 that are each connected to and in fluid communication with the barrel 111. One of the tubes 112 has an inlet 113 and the other one of the tubes 112 has an outlet 114. The inlet 113 is adapted to be connected to a high-pressure liquid containing device (not shown).
Referring to FIGS. 1 and 2, the conventional pressure reducing device includes a guide screw 121, a threaded ring 123 mounted threadedly to the guide screw 121, and a pair of rods 124 each connected to the threaded ring 123. With further reference to FIG. 3, the guide screw 121 and the threaded ring 123 are extended in the barrel 111, and each of the rods 124 is extended into a corresponding one of the tubes 112.
The foregoing conventional pressure reducing device includes the following disadvantages:
1) One or both of the rods 124 may abut against an inner surface of the corresponding tube 112 to hinder rotation of the threaded ring 123. The rods 124 may therefore experience substantial and repeated bending stress during operation of the conventional pressure reducing device, which may lead to damage and eventual failure of the device.
2) The spaces between the threaded ring 123 and either the inner wall of the barrel 111 or the guide screw 121 may be continually exposed to high pressure fluid from the inlet 113. This may allow leakage between the threaded ring 123 and either the guide screw 121 or the inner wall of the barrel 111.
3) The barrel 111 and the tubes 112 may be difficult to access and clean, leading to accumulation of dust or blockages that may reduce the effectiveness of the conventional pressure reducing device. If the blockages are severe, the entire device may need to be replaced, adding unnecessarily to operating costs of the system.